Tom New: Silence from other galaxies is deafening

Two separate news items recently focused attention on one big question: Are we alone in the universe?

First, physicist Stephen Hawking and Russian billionaire Yuri Milner announced a partnership to search for signs of life on other worlds. Then NASA revealed the discovery of an Earth-like planet within cosmic shouting distance. Central to both stories is this question: Are there other civilizations out there, or is our blue marble unique in the cosmos?

So far, the evidence suggests we’re alone. Despite years of listening to the heavens through initiatives such as SETI (Search for Extraterrestrial Intelligence), and despite a popular culture that celebrates contact with “others,” we haven’t heard anything from out there. Not a peep.

In fact, that “not a peep” has a name: the Great Silence. The term was coined in the 1950s, when a group of physicists was discussing the high probability of intelligent life existing on other planets. One of them, Nobel Prize winner and physicist Enrico Fermi, is said to have blurted out: “Where are they?” That question came to be known as the Fermi paradox, or the Great Silence.

This is the problem in a nutshell: Given the potential for intelligent life out there, why haven’t we heard anything? Scientists are puzzled, because the numbers don’t seem to add up.

A formula called the Drake equation estimates the number of potential Earth-like planets that could give rise to technologically advanced civilizations in our galaxy, the Milky Way. With an estimated 100 billion stars in the galaxy, most with multiple planets, the Drake equation suggests there may be between 1,000 and 100,000 advanced civilizations in the Milky Way.

That’s quite a range, but given the potential for otherworldly civilizations to flourish and presumably make scientific progress, why haven’t we detected them? Yes, distances are vast, but given the cosmic timelines, if there are signals emanating from a tech-capable civilization, where are those signals?

There are any number of possible explanations. Maybe we are alone, and unique in the cosmos. This plays well with people who think our species is somehow the peak of evolutionary maturity, despite our tendency to harm ourselves and the species around us.

From a different perspective, maybe we’re alone in the universe because other civilizations have extinguished themselves, and we haven’t reached that point. Yet.

The timing isn’t right. Maybe there have been other technologically advanced civilizations out there that have come and gone over the eons, but we happen to be listening during a quiet period.

Perhaps the most intriguing explanation for the Great Silence is that maybe we’re listening the wrong way, or listening for the wrong things.

Which brings us back to Stephen Hawking.

Some months ago, Hawking cautioned against the potential dangers of artificial intelligence. If AI were to become smarter than the species developing it, maybe it would decide to eliminate the biological variable. That would be us. Or, the two species might assimilate, for instance by uploading human consciousness into a molecular computer (the Borg reference is intended).

If assimilation occurs — or has happened on other worlds — maybe biotechnological communication evolves in ways we can’t detect. A fly on a wall registers passing pressure waves in the air, and on some level, may even be aware that they’re spaced irregularly. The fly would have no idea that humans interpret those passing pressure waves as speech.

Similarly, there may be a rich conversation of cosmic voices all around us, but they’re so far beyond our comprehension that we can’t understand them.

So, is any of this important? Who really cares if some silicon-based intelligence on a planet 43 light years away is going about its daily chores?

Back to Stephen Hawking once again.

“There is no bigger question,” Hawking said. “We are intelligent, we are alive, we must know.”